Kerr can thrive as long as he is in charge of his emotions, with a laser focus onto his next win. Without that, his self and identity fracture apart into nothingness. He can barely recognize himself so lost and spiraling. Dawn emboldens him, nudges him to stay upbeat. But the minute she tells him to get over being mopey because of one lost match, he loses it. Ramming down a door in fury, he never inflicts violence on her. But the creased nerves, the emotional disruption hang in the air. Even when they are pleasant and agreeable and having a wonderful time, you sense things poised to go south very soon. Kerr and Dawn aren’t healthy for each other; his best buddy and longtime coach, Mark Coleman (Ryan Bader) sees the damage, toxicity spilling through the on-off-on relationship. While Kerr seems to operate best in disconnected solitude, Coleman is his complete opposite, a true-blue family man. Bader is terrific in the minimal Safdie gives him. As he slips back into his contestant roots, one final bid to do something fulfilling that’s also essential for raising his family, Bader quietly sneaks up on you.